Known hybrid power systems with hybrid drives or drive trains may include an internal combustion engine, and electric motor or machine combination. The engine may include a diesel or gasoline engine driving a power train and/or charging an energy storage system, for example, a high voltage battery, wherein the engine and the high voltage battery provide plural drive sources to a hybrid vehicle. It is also known to arrange an internal combustion engine and/or one or more electric machines in such a manner that they can be operatively connected to each other by gears, for example, planetary gear sets or the like, and couplings. Different operating states of the combustion engine and electric motor(s) can effect fuel consumption, dynamic performance of the vehicle, and pollutant emissions. These techniques focus on interactions between the engine, transmission and motor/generator during active driving.
In hybrid vehicles it is important to obtain higher more efficient use of fuel, and improve mileage per gallon of fuel consumed. This may be accomplished by a traction motor driving the vehicle as much as possible. In order to utilize the traction motor instead of burning fuel, it is necessary for a traction motor operating as a generator to recapture as much power as possible when the vehicle is being braked. Recapturing power is limited because a transmission gear ratio is linked to the speed range of a combustion engine, even though traction motor operation during regeneration may have a wider range of operation speeds.